Optical cohrence tomography (OCT)

Application and development of ultrafast MHz OCT systems

OCT is a noninvasive Imaging modality which is typically used for high resolution (~10µm), three dimensional imaging of scattering tissue. By using home built FDML laser technology we achieve imaging speeds of several million depth scans per second, which is one to two orders of magnitude higher than current commercially available systems (MHz-OCT).

Figure 1: OCT images taken by a homemade 1300nm-3MHz OCT system using an FDML laser as the light source. Images of the thenar, dorsum of the hand and fingertip are shown.

These high imaging speeds already proved to be very useful in clinical applications, by reducing acquisition times and therefore reducing motion artifacts. But the high speed also gives access to the phase of the detected light and will thus allow the use of new numerical approaches for image quality enhancement and functional imaging with Swept-Source-OCT.

Our working group is conducting research in the field of OCT to develop new technologies and to identify possible fields of application.

The focus areas are:

  • MHz-OCT - Ultra-fast OCT imaging with several million depth scans per second
  • LARA-OCT - Large area robotically assisted OCT
  • VR-OCT - Real-time computation and rendering of entire OCT volumes in a virtual environment
  • Eye OCT - application of MHz-OCT to the eye for visualization of the retina or the anterior segment of the eye
  • Phase sensitive OCT - enhancement of the information content of an OCT image by adding phase contrast
  • Multispectral OCT - combination of RGB and OCT images for improved visualization of morphological structures

related Publications

2005

Robert Huber, Kenji Taira, Maciej Wojtkowski, Tony H. Ko, James G. Fujimoto, and Kevin Hsu,
Figh-speed frequency swept light source for Fourier domain OCT at 20 kHz A-scan rate, in Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine IX , Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, 042005. pp. 96-100.
DOI:10.1117/12.592552
Bibtex: BibTeX
@inproceedings{10.1117/12.592552,
author = {Robert Huber and Kenji Taira and Maciej Wojtkowski and Tony Hong-Tyng Ko and James G. Fujimoto and Kevin Hsu},
title = {{High-speed-frequency swept light source for Fourier domain OCT at 20-kHz A-scan rate}},
volume = {5690},
booktitle = {Coherence Domain Optical Methods and Optical Coherence Tomography in Biomedicine IX},
editor = {Valery V. Tuchin and Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {96 -- 100},
abstract = {We demonstrate a high-speed tunable, continuous wave laser source for Fourier domain OCT.  The laser source is based on a fiber coupled, semiconductor optical amplifier and a tunable ultrahigh finesse, fiber Fabry Perot filter for frequency tuning.  The light source provides frequency scan rates of up to 20,000 sweeps per second over a wavelength range of >70 nm FWHM at 1330 nm, yielding an axial resolution of ~14 μm in air.  The linewidth is narrow and corresponds to a coherence length of several mm, enabling OCT imaging over a large axial range.},
keywords = {swept source, Fourier Domain, OCT, tunable laser, Spectral Domain, frequency domain imaging, OFDI, sweep},
year = {2005},
doi = {10.1117/12.592552},
URL = {https://doi.org/10.1117/12.592552}
}